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Full text of "The manufacture and properties of iron and steel"

30                                '            INTBODUCTION".
an inch in thickness, as filling pieces between riveted work of one and one-half inches in thickness. Although this was simply a washer, and although any storehouse could supply suitable sheets of ordinary steel, the inspector required that the steel be made especially for the place, and the same in composition and physical characteristics as the angles and plates, although this necessitated the making of contracts with sheet mills and the delay of the erecting work. The honest business man wants a competent inspector who knows how to get what is called for; who' may examine a turnbuekle with a magnifying glass, but pays less attention to an angle for a hand railing; who hammers a fire-box sheet, but is lenient with a gusset-plate.
The proper way would be to place the inspection in the hands of a competent man, with full authority to make concessions or extra tests during the progress of the work. Under any system, most of the work will probably be done by subordinates who are not qualified to decide all questions that may arise, but the chiefs of American inspection bureaus are capable of meeting all responsibility. ' 
In former clays surface inspection was the most important function of the inspector; to-day it is the least of his duties. In fact, it has become such a matter of form that there is a tendency toward its complete abolition. There is much to be said in favor of such a step, for if an imperfection is discovered in any piece of steel, no matter if it has passed a dozen inspectors, the defective member must be replaced. Granting this condition, it is better for the. manufacturer to reject unsuitable bars at the mill than to have them thrown out at distant points, and it will be to his interest to inspect all material before shipment.
The mill inspection is so< carefully done in well-conducted works that it is unusual for an outside inspector to reject bars, and it would be still more thoroughly performed if the manufacturer knew the responsibility rested with him alone. .Where the material is to be passed upon by an outside inspector, the natural tendency is to let doubtful bars.go by, since the responsibility of their acceptance is to rest upon other shoulders. These facts are so well known that some of the best engineers in the country do not make any surface inspection.
Whether this practice be generally accepted or not, it is eminently desirable that the inspection bureaus should arrange to examine the